Exhaust system for internal combustion engine

ABSTRACT

The present disclosure provides an exhaust system for an internal combustion engine, the exhaust system comprising a first exhaust pipe, a muffler and a second exhaust pipe, and the muffler is mounted between the first exhaust pipe and the second exhaust pipe, the first exhaust pipe is located upstream of the muffler, and the second exhaust pipe is located downstream of the muffler; the second exhaust pipe comprises a single exhaust pipe, the single exhaust pipe having one end connected to a downstream end of the muffler, and the single exhaust pipe being provided with a plurality of connecting holes; or, the second exhaust pipe comprises the single exhaust pipe and a dual exhaust pipe branch, the single exhaust pipe having one end connected to the downstream end of the muffler and the other end connected to the dual exhaust pipe branch.

CROSS REFERENCE TO THE RELATED APPLICATION

This application is based upon and claims priority to Chinese Patent Application No. 201921694694.8, filed on Oct. 11, 2019, the entire content of which is incorporated herein by reference.

FIELD

The present disclosure relates to the automotive field, and in particular to an exhaust system for an internal combustion engine.

BACKGROUND

In the automotive field, an exhaust system is a system for controlling emissions and noises of a vehicle, and is arranged under an entire chassis of the vehicle, connected to an exhaust manifold of an engine, and suspended below a floor of a vehicle body. Therefore, the exhaust system usually has a complicated shape trend, but it is also a key component related to the vibration and noises of the whole vehicle.

A muffler is mainly used to reduce exhaust noises of the engine and ensure that high-temperature waste gases are exhausted safely and efficiently. As a part of an exhaust pipe, the muffler shall ensure smooth gas exhaust, little resistance, and sufficient strength.

FIG. 1 is a schematic structural diagram of an exhaust system for an internal combustion engine in the prior art. FIG. 2 is a front view of the exhaust system for an internal combustion engine in the prior art. FIG. 3 is a perspective view of another exhaust system for an internal combustion engine in the prior art.

As shown in FIG. 1 to FIG. 3, a conventional exhaust system for an internal combustion engine usually comprises at least two mufflers 20, which increase the weight of an exhaust system for a gasoline engine, need more installation space, and also greatly increase costs.

In view of this, embodiments of the present disclosure have improved the structure of the exhaust system for a gasoline engine in order to overcome the above problems.

SUMMARY OF THE DISCLOSURE

The problem to be solved in the present disclosure is to provide an exhaust system for an internal combustion engine to overcome the defects of an increase in the weight of the exhaust system and a need of more installation space caused by a large number of mufflers mounted at an exhaust system for an internal combustion engine in the prior art.

The problem mentioned above is solved in the present disclosure by the following embodiments:

an exhaust system for an internal combustion engine, comprising: a first exhaust pipe, a muffler and a second exhaust pipe, and the muffler is mounted between the first exhaust pipe and the second exhaust pipe, the first exhaust pipe is located upstream of the muffler, and the second exhaust pipe is located downstream of the muffler;

the second exhaust pipe comprises a single exhaust pipe, the single exhaust pipe having one end connected to a downstream end of the muffler, and the single exhaust pipe being provided with a plurality of connecting holes; or

the second exhaust pipe comprises the single exhaust pipe and a dual exhaust pipe branch, the single exhaust pipe having one end connected to the downstream end of the muffler and the other end connected to the dual exhaust pipe branch, and the single exhaust pipe and the dual exhaust pipe branch being respectively provided with a plurality of connecting holes.

According to an embodiment of the present disclosure, the second exhaust pipe has a length greater than 1 meter.

According to an embodiment of the present disclosure, the connecting hole is a round hole, and the total equivalent area of the round hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

According to an embodiment of the present disclosure, the connecting hole is a rectangular hole, and the total equivalent area of the rectangular hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

According to an embodiment of the present disclosure, the connecting hole is of a micro-perforation structure, and the total equivalent area of the micro-perforation structure is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

According to an embodiment of the present disclosure, an external heat shield is provided on the connecting hole, the external heat shield is an enclosed heat shield or a heat shield provided with an open pore, and the total equivalent area of the open pore is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

According to an embodiment of the present disclosure, a Helmholtz resonator is provided on the connecting hole, and the Helmholtz resonator has a volume smaller than or equal to 1 L.

According to an embodiment of the present disclosure, the Helmholtz resonator is provided in the form of a neck patch, a neck pipe or other transfer passage.

According to an embodiment of the present disclosure, the first exhaust pipe is further provided with an on-pipe noise-regulating valve.

The positive progressive effect of the present disclosure lies in that

the exhaust system for a gasoline engine of the present disclosure can achieve the effects of weakening vibration and reducing noises only by using one muffler at a cold end. Moreover, a pore, the HHR (Helmholtz resonator) and a perforated plate are used to restrain standing waves. The exhaust system for a gasoline engine reduces the volume of the muffler, the overall weight, and the manufacturing cost.

The exhaust system for a gasoline engine uses a long exhaust pipe and has a better acoustic performance at an idle speed and a low rotating speed range.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features, properties and advantages of the present disclosure will become more apparent from the following description of the embodiments with reference to the accompanying drawings, and the same reference numerals denote the same features throughout the figures. In the figures:

FIG. 1 is a perspective view of an exhaust system for an internal combustion engine in the prior art.

FIG. 2 is a front view of the exhaust system for an internal combustion engine in the prior art.

FIG. 3 is a perspective view of another exhaust system for an internal combustion engine in the prior art.

FIG. 4 is a perspective view of an exhaust system for an internal combustion engine according to an embodiment of the present disclosure.

FIG. 5 is a front view of the exhaust system for an internal combustion engine according to an embodiment of the present disclosure.

FIG. 6 is a perspective view of an exhaust system for an internal combustion engine according to another embodiment of the present disclosure.

FIG. 7 is a first schematic diagram of a connecting hole in an exhaust system for an internal combustion engine of the present disclosure.

FIG. 8 is a second schematic diagram of the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 9 is a third schematic diagram of the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 10 is a first schematic diagram of an external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 11 is a second schematic diagram of the external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 12 is a third schematic diagram of the external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 13 is a first schematic diagram of a Helmholtz resonator arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 14 is a second schematic diagram of the Helmholtz resonator arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

FIG. 15 is a schematic diagram of an on-pipe noise-regulating valve arranged on a first exhaust pipe of the exhaust system for an internal combustion engine of the present disclosure.

FIG. 16 is a schematic structural diagram of the on-pipe noise-regulating valve.

REFERENCE NUMERALS

First exhaust pipe 10 Muffler 20 Second exhaust pipe 30 Single exhaust pipe 31 Dual exhaust pipe branch 32 Connecting hole 33 External heat shield 40 Open pore 41 Helmholtz resonator 50 On-pipe noise-regulating valve 60 Pipe body 61 Torsion return spring 62 Partition 63 Maximum position p2 Initial position p1

DETAILED DESCRIPTION OF EMBODIMENTS

In order to make the object, features and advantages mentioned above of the present disclosure more apparent and easily understood, particular embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

Embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. Reference will now be made in detail to embodiments of the present disclosure, with examples thereof being illustrated in the accompanying drawings. The same reference numerals used throughout the figures denote identical or similar parts wherever possible.

Furthermore, although the terms used in the present disclosure are selected from well-known common terms, some of the terms mentioned in the description of the present disclosure may have been selected by the applicant according to his or her determination, and the detailed meaning thereof is described in the relevant section described herein.

Furthermore, the present disclosure should be understood, not simply by the actual terms used but also by the meanings encompassed by each term.

FIG. 4 is a perspective view of an exhaust system for an internal combustion engine according to an embodiment of the present disclosure. FIG. 5 is a front view of the exhaust system for an internal combustion engine according to an embodiment of the present disclosure.

As shown in FIG. 4 and FIG. 5, disclosed is an exhaust system for an internal combustion engine, the exhaust system comprising a first exhaust pipe 10, a muffler 20 and a second exhaust pipe 30, and the muffler 20 is mounted between the first exhaust pipe 10 and the second exhaust pipe 30, the first exhaust pipe 10 is located upstream of the muffler 20 and the second exhaust pipe 30 is located downstream of the muffler 20.

The second exhaust pipe 30 comprises a single exhaust pipe 31 and a dual exhaust pipe branch 32, the single exhaust pipe 31 has one end connected to a downstream end of the muffler 20, the single exhaust pipe 31 has the other end connected to the dual exhaust pipe branch 32, and the single exhaust pipe 31 and the dual exhaust pipe branch 32 are respectively provided with a plurality of connecting holes 33.

FIG. 6 is a perspective view of an exhaust system for an internal combustion engine according to another embodiment of the present disclosure.

As shown in FIG. 6, the second exhaust pipe 30 in the exhaust system for an internal combustion engine can further comprise a single exhaust pipe 31 only, the single exhaust pipe 31 has one end connected to the downstream end of the muffler 20, and the single exhaust pipe 31 is provided with a plurality of connecting holes 33.

In one embodiment, the second exhaust pipe 30 herein is located at the downstream end of the muffler 20, with a length greater than 1 meter.

FIG. 7 is a first schematic diagram of a connecting hole in an exhaust system for an internal combustion engine of the present disclosure. FIG. 8 is a second schematic diagram of the connecting hole in the exhaust system for an internal combustion engine of the present disclosure. FIG. 9 is a third schematic diagram of the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

As shown in FIG. 7 to FIG. 9, the connecting hole 33 can be arranged in various shapes, for example, the connecting hole 33 may be a round hole, and the total equivalent area of the round hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm. Or, the connecting hole 33 may be a rectangular hole or a prolate oblong hole, and the total equivalent area of the rectangular hole or the prolate oblong hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm. Or, the connecting hole 33 may be of a micro-perforation structure, and the total equivalent area of the micro-perforation structure is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

FIG. 10 is a first schematic diagram of an external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure. FIG. 11 is a second schematic diagram of the external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure. FIG. 12 is a third schematic diagram of the external heat shield arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

As shown in FIG. 10 to FIG. 12, particularly, an external heat shield 40 may also be arranged on the connecting hole 33, the external heat shield 40 may be an enclosed heat shield or a heat shield provided with an open pore 41, and the total equivalent area of the open pore is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.

The external heat shield 40 can be provided with an open hole 41 or uniformly provided with a plurality of open pores 41 in an annular way. The enclosed heat shield may also be provided with glass wool to prevent the enclosed heat shield from leaking unexpectedly.

FIG. 13 is a first schematic diagram of a Helmholtz resonator arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure. FIG. 14 is a second schematic diagram of the Helmholtz resonator arranged at the connecting hole in the exhaust system for an internal combustion engine of the present disclosure.

As shown in FIG. 13 and FIG. 14, further, the Helmholtz resonator 50 can further be provided on the connecting hole 33, and the Helmholtz resonator 50 has a volume smaller than or equal to 1 L. The area of the connecting hole 33 is smaller than or equal to that of a round hole with a diameter of 20 mm.

The Helmholtz resonator 50 can be provided in the form of a neck patch, a neck pipe or other transfer passage. A neck patch of an inner transfer passage has an equivalent area smaller than or equal to the area of a round ring with a diameter of 15 mm. A neck pipe of the inner transfer passage has an equivalent area of smaller than or equal to the area of a round ring with a diameter of 15 mm.

Or, the Helmholtz resonator can be provided in the form of other transfer passage made of a metal plate, with an equivalent area smaller than or equal to the area of a round ring with a diameter of 15 mm.

FIG. 15 is a schematic diagram of an on-pipe noise-regulating valve arranged on a first exhaust pipe of the exhaust system for an internal combustion engine of the present disclosure. FIG. 16 is a schematic structural diagram of the on-pipe noise-regulating valve.

As shown in FIG. 15 and FIG. 16, still further, the first exhaust pipe 10 is further provided with an on-pipe noise-regulating valve 60. The flow of a fluid is regulated, guided or controlled by opening, closing or partially blocking various passages. The on-pipe noise-regulating valve can improve the noise sequence by regulating a back pressure of the exhaust system.

The on-pipe noise-regulating valve 60 comprises a pipe body 61, at least one rotating shaft (not shown in the figures), a torsion return spring 62, and a partition 63 which is connected to the rotating shaft. An appropriate air flow can drive the partition 63 to rotate around the rotating shaft to a corresponding position. The maximum air flow can drive the partition to rotate to the maximum position p2, and the partition returns to an initial position p1 when the air flow is relatively small or where there is no air flow.

In summary, the exhaust system for a gasoline engine in the present disclosure can achieve the effects of weakening vibration and reducing noises only by using one muffler at a cold end. The exhaust system for a gasoline engine reduces the volume of the muffler, the overall weight, and the manufacturing cost.

The exhaust system for a gasoline engine uses a long exhaust pipe and has a better acoustic performance at an idle speed and a low rotating speed range. 

What is claimed is:
 1. An exhaust system for an internal combustion engine, comprising: a first exhaust pipe, a muffler and a second exhaust pipe, wherein the muffler is mounted between the first exhaust pipe and the second exhaust pipe, the first exhaust pipe is located upstream of the muffler, and the second exhaust pipe is located downstream of the muffler; the second exhaust pipe comprises a single exhaust pipe, the single exhaust pipe having a first end connected to a downstream end of the muffler, and the single exhaust pipe being provided with a plurality of connecting holes; or the second exhaust pipe comprises the single exhaust pipe and a dual exhaust pipe branch, the single exhaust pipe having the first end connected to the downstream end of the muffler and a second end connected to the dual exhaust pipe branch, and the single exhaust pipe and the dual exhaust pipe branch being respectively provided with a plurality of connecting holes.
 2. The exhaust system for an internal combustion engine of claim 1, wherein the second exhaust pipe has a length greater than 1 meter.
 3. The exhaust system for an internal combustion engine of claim 1, wherein a connecting hole is a round hole, and the total equivalent area of the round hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.
 4. The exhaust system for an internal combustion engine of claim 1, wherein a connecting hole is a rectangular hole, and the total equivalent area of the rectangular hole is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.
 5. The exhaust system for an internal combustion engine of claim 1, wherein a connecting hole is of a micro-perforation structure, and the total equivalent area of the micro-perforation structure is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.
 6. The exhaust system for an internal combustion engine of claim 1, wherein an external heat shield is arranged on the connecting hole, the external heat shield is an enclosed heat shield or a heat shield provided with an open pore, and the total equivalent area of the open pore is greater than or equal to that of a round hole with a diameter of 2 mm and smaller than that of a round hole with a diameter of 30 mm.
 7. The exhaust system for an internal combustion engine of claim 1, wherein a Helmholtz resonator is provided on the connecting hole, and the Helmholtz resonator has a volume smaller than or equal to 1 L.
 8. The exhaust system for an internal combustion engine of claim 7, wherein the Helmholtz resonator is provided in a form of a neck patch, a neck pipe or other transfer passage.
 9. The exhaust system for an internal combustion engine of claim 1, wherein the first exhaust pipe is further provided with an on-pipe noise-regulating valve. 